Processing apparatus

ABSTRACT

Apparatus for processing samples, such as tissue samples, including a rotatable table which carries either the samples or solutions in which the samples are to be immersed. The table is rotatable between a series of sample processing stations and is also arranged for axial movement between positions at which a sample is and is not respectively immersed in a solution. A single reversible motor is operable to both rotate the table and cause axial movement thereof. The motor drives a spindle having a double helix and also drives the table through a one way clutch arranged so that in one mode of operation the motor rotates both the spindle and the table and in another mode it rotates the spindle only. In the latter case the table is caused to move up and down the spindle as a result of cooperation between a follower and the helix tracks of the spindle.

This invention relates to apparatus for processing samples and isparticularly but not exclusively concerned with such apparatus as usedto process tissue samples. By way of example, such apparatus is used inhospital pathology departments and laboratories to prepare samples formicroscopic examination - e.g., examination through an electronmicroscope. Example samples prepared in that way are skin tissues ortissues from organs such a the liver, kidney, or heart. It will beconvenient to hereinafter describe the invention with particularreference to tissue processing apparatus, but it is to be understoodthat the invention has other applications. In that regard, the apparatusaccording to the invention can be used for biological and non-biologicalpurposes.

Apparatus of the foregoing kind is generally of complex and expensiveconstruction. Indeed, the cost of satisfactory apparatus is soprohibitive that some organizations continue to manually process tissuesamples and that is a labourious and time consuming operation.

It is an object of the present invention to provide relatively simpleapparatus which enables convenient processing of a sample or a pluralityof samples. It is a further object of the invention in a particular formto provide such apparatus which enables convenient processing of tissuesamples. It is yet another object of the invention to provide suchapparatus which requires only one drive motor to perform a plurality offunctions.

According to the present invention, there is provided a sampleprocessing apparatus including, a carousel mounted for rotation and forback and forth movement in the direction of the axis of said rotation,and control mechanism operable to cause said rotation and said axialmovement of the carousel, said control mechanism including, a drivemotor which operates both in a forward mode and a reverse mode andtransmission means which interconnects said carousel and said drivemotor, and said transmission means is responsive to operation of saidmotor in one said mode to cause said carousel rotation and is responsiveto operation of said motor in the other said mode to cause said carouselaxial movement.

In a preferred arrangement the carousel is mounted on an upstandingrotatable spindle having a two way helix formed therealong and afollower is connected to the carousel so as to engage with the helix.That engagement is such that the carousel is caused to move axially onor along the spindle when there is relative rotation between the spindleand carousel. It is also preferred that the drive connection between themotor and spindle includes a one way clutch which operates to allow thespindle to rotate relative to the carousel in one direction and toprevent such relative rotation in the opposite direction.

The essential features of the invention and further optional features,are described in the following passages of the specification which referto the accompanying drawings. The drawings however, are merelyillustrative of how the invention might be put into effect, so that thespecific form and arrangement of the features (whether they be essentialor optional features) shown is not to be understood as limiting on theinvention.

In the drawings:

FIG. 1 is a semidiagrammatic view of one form of apparatus according tothe invention;

FIG. 2 is a view taken along line II--II of FIG. 1;

FIG. 3 is a side elevational view of a container or vias as used withapparatus according to the invention;

FIG. 4 is a diagrammatic view of part only of the central spindle of theapparatus shown in FIG. 1;

FIG. 5 is an enlarged cross sectional view taken along line V--V of FIG.1;

FIG. 6 is an enlarged cross sectional view taken along line VI--VI ofFIG. 1;

FIG. 7 is a cross sectional view taken along line VII--VII of FIG. 6.

Apparatus according to the invention includes a rotatable carousel ortable which carries either the sample or samples or at least onecontainer in which the or each sample is to be immersed. In theparticular form shown in the accompanying drawings the rotatable table 1is adapted to carry a plurality of containers or vials 2, but asindicated above other arrangements could be adopted. The apparatusfurther includes a single reversible motor 3 which is operable to causethe table 1 to rotate during one part of the sequence of operations andto move axially during another part of that sequence.

The example arrangement shown in the drawings is particularly suited forprocessing tissue samples, and in that arrangement the rotatable tableis circular and is adapted to carry a plurality of open-toppedcontainers or vials 2. The vials 2 are arranged in a circle and may beattached to or mounted on the table 1 in any suitable fashion. In thearrangement particularly shown however, the table 1 includes a pluralityof mounting stations in the form of circular openings 4 each of which isconnected to the table periphery through a passage 5 which has a widthless than the diameter of the opening 4 (FIG. 2). As shown in FIG. 3,each vial 2 has a neck portion 6 of reduced diameter adjacent its lowerend and that neck portion 6 has a diameter such as to neatly fit withinan opening 4. The passage 5 however, is narrower than that diameter andthe vial 2 and/or the table 1 has sufficient resilience or flexibilityto allow the neck portion 6 to be pushed through the passage 5 for snapengagement within the opening 4. Other arrangements could be adopted toachieve the same result.

If desired, the table 1 may be arranged to carry two or moreconcentrical circles of vials 2. The table 1 is preferably mounted on anan upstanding column 7 as hereinafter described in detail. In otherarrangements however, the column 7 may be arranged at an angle or it mayextend horizontal rather than vertical as shown.

A sample supporting member 8 is arranged to overlie the table 1 and isadapted to carry at least one sample so that it may be immersed asrequired in a vial 2. The supporting member 8 as shown is in the form ofa plate-like cover which is mounted so as to be restrained againstmovement in any direction. Nevertheless, means may be provided wherebythe member 8 may be detached from the rest of the apparatus to allow,for example, removal and/or attachment of tissue samples. Furthermore,in other arrangements the member 8 could be in the form of an arm whichoverhangs the table 1 and such an arm could carry one or more samples.Also, in any particular arrangement there may be a plurality of sucharms and in that event the various arms may be of the same or differentlength so as to serve the same circle or different circles of vials 2.

Any suitable means may be adopted for attaching samples to the covermember 8. In the arrangement shown the cover member 8 has a plurality ofsample stations 9 which correspond in position and number to theunderlying vials 2. That is, it is possible to have a respective samplelocated above each vial 2 for immersion therein. The sample retainingmeans at any station 9 may include, as shown, a rod 10 which dependsfrom the undersurface of the cover member 8 and a cage or basket 11attached to the lower end of the rod 10 and adapted to hold a tissuesample (not shown).

Preferably, the upper end of each rod 10 is secured to a cap 12 which islocated within a hole formed through the cover member 8 and which isremovable from that hole to enable a sample to be placed in or removedfrom the respective cage or basket 11. That is, the cap 12 is accessibleat the top of the cover member 8 so that the attached sample retainer10,11 can be lifted upwardly through the associated hole and therebyseparated from the cover member 8.

Control mechanism is provided whereby the table 1 can be moved axiallyup and down to respectively position a sample within a vial 2 as shownin broken line in FIG. 1, and separate the vial 2 from the sample asshown in full line in FIG. 1. In an alternative arrangement which is notshown, the cover member 8 could be moved towards and away from the table1 to achieve the same result, but the former arrangement is favoured inthe apparatus herein described. An annular pad 13 of resilient materialsuch as sponge rubber may be provided on the undersurface ofthe covermember 8 at each sample station 9 so as to be engagable against the rimsurrounding the open mouth 14 of an underlying vial 2. That is, when thetable 1 is raised to the sample immersion position as shown in brokeline in FIG. 1 the rim of each vial 2 engages a respective pad 13 sothat the open mouth 14 of the vial 2 is substantially sealed.

For the purpose of processing tissue samples, each vial 2 of the groupcarried by the table 1 may contain a different solution within which thesample is to be sequentially immersed. It is generally preferred toeffect some agitation of the sample and/or the vial contents during theimmersion so as to ensure that the solution will have maximum affect onthe sample. That may be achieved through use of a piezo crytal 15attached to each sample retainer rod 10 and arranged to be energized byappropriate means (not shown). The agitating means can take other formshowever, and by way of example could be any suitable electrical,electrical/mechanical, or electro-magnetic device. In the example shown,each rod 10 is attached to its respective cap 12 through such a crystal15.

Control mechanism for the table 1 includes the reversible drive motor 3and transmission mean interconnecting the drive motor 3 and table 1. Themotor 3 operates in either a forward mode or a reverse mode, and thetransmission means is arranged so that it responds to one mode ofoperation to cause rotation of the table 1 and responds to the othermode to cause up and down movement of the table 1. In a typical sequenceof operations, the table 1 is raised to the limit of its upward traveland held there for a suitable period of time, it is then lowered androtated through a predetermined distance while in the lowered positionto be conditioned for commencement of another sequence of operations.

In the particular arrangement shown, the transmission means includes anupstanding spindle 7 having a two-way helix formed therein. That is, thehelix includes two intersecting helical tracks 16 and 17 which extendalong the spindle 7 at opposite angles as shown in FIG. 4. A follower 18is arranged to engage with either helix track 16 or 17 and is attachedto or forms part of the table 1. The spindle 7 forms the aforementionedsupport column for the table 1 and it is mounted for rotation relativeto a support structure which may include or be attached to a base plate19 of the apparatus. As shown, a lower portion 20 of the spindle 7 mayproject downwardly through a support plate 21 which is located above thebase plate 19 and is rotatably connected to that support plate 21through a suitable bearing. The drive motor 3 may be connected direct tothe lower portion 20 of the spindle 7 in any suitable fashion, but theconnection shown includes a belt 22 and cooperating pulleys 23 and 24secured to the motor 3 and spindle 7 respectively.

As shown in FIG. 5, in the particular arrangement shown the follower 18includes a cylindrical body 25 and a flat tongue portion 26 whichprojects from one end of the body 25. The body 25 is located within abore 27 of a sleeve 28 which is secured to the table 1 so as to rotatewith that table 1 and the tongue portion 26 projects out of the sleeve28 as shown in FIG. 1 so as to locate within either of the helicaltracks 16 and 17. The arrangement is such that the follower body 25 canrotate about its longitudinal axis relative to the sleeve 28 and therebyallow the tongue portion 26 to adapt itself to the slope of theparticular track 16 or 17 within which it locates.

The transmission means also includes a drive connection between themotor 3 and the table 1 which includes a one-way clutch 29 (e.g., asprag clutch) so that the table 1 is caused to rotate when the motor 3is turning in one particular direction. In the particular arrangementshown, that drive connection includes a drive plate 30 which forms partof the rotatable mounting of the spindle 7 on the support plate 21. Thatis, the drive plate 30 is connected to the support plate 21 through theaforementioned bearing and the one-way clutch 29 is located between thedrive plate 30 and the spindle 7. A thrust bearing may be providedbetween the spindle 7 and the drive plate 30 to facilitate relativerotation of those components and take the downward load of the spindle7.

Drive means is provided between the drive plate 30 and the table 1whereby rotary motion of the drive plate 30 is transmitted to thetable 1. That drive means may be releasable as a consequence of axialmovement of the table 1 relative to the drive plate 30, but in thearrangement shown it remains effective at all axial positions of thetable 1. In the arrangement shown, the drive means includes a coupling,part of which is formed by a rod 31 secured to the drive plate 30 at alocation radially outwards of the spindle 7 and extending upwardly fromthe drive plate 30 in a direction of the spindle axis. The rod 31slidably locates within a passage 35 provided in the table sleeve 28 sothat the sleeve 28 moves along the rod 31 during travel of the table 1up and down the spindle 7. It is to be appreciated that the apparatuscould include two or more rods 31 rather than one as shown.

It is preferred that the motor 3 is a pulse operated stepper motor andthat operation of the motor 3 is controlled through suitable circuitrywhich may, for example, form part of a micro-processor. The controlcircuitry will be arranged to determine the desired sequence ofoperations and the time delay at various stages of that sequence. It mayalso includes a monitoring function to ensure that certain operationsare completed before the apparatus is directed to perform subsequentstages.

Assuming the table 3 is in the lowered position, it may be releasablyretained in a particular rotational position by detent means . As shown,a spring loaded detent ball 32 may be used for that purpose and thatball 32 is carried by the support structure and arranged to locate inany of a plurality of indexing recesses 33 formed in a cylindricalsurface 34 of the drive plate 30. It is possible to use locators havinga form different to that of the recesses 33 as shown. For example, theycould be in the form of peripheral slots. The number of recesses 33 andtheir spacing will be selected to suit the number and location of thesample processing stations of the apparatus. By way of example, theremay be twenty stations located at regularly spaced intervals. That is,at each rotational position of the table 1 as determined by the detentball 32, a vial 2 carried by that table 1 is located directly beneath aparticular sample station 9 of the cover member 8.

It is preferred to provide means for positively restraining the detentball 32 against disengagement from an indexing recess 33 while the table1 is being moved between its raised and lowered positions, or whilesample procesing is actually taking place. One manner of achieving thatretention is shown by FIGS. 6 and 7 and in that particular arrangement asolenoid 36 is operative to positively prevent withdrawal of the detentball 32 from the recess engaging position as shown by FIG. 6.

In the FIGS. 6 and 7 arrangement the detent ball 32 is urged outwards ofits mounting 37 by means of a plunger 38 and associated spring 39. Thesolenoid 36 is operative to drive a locking member 40 into acircumferential recess 41 provided around the plunger 38 and therebyprevent disengagement of the detent ball 32 from a recess 33. In thearrangement shown the solenoid 36 is spring biased into that lockingcondition and when the solenoid 36 is energized it operates to withdrawthe member 40 from the detent locking position and thereby permitdisengaging movement of the detent ball 32.

The solenoid 36 can be connected into the control circuitry of theapparatus so as to lock and free the detent ball 32 at appropriate timeswithin an operating sequence. Operator sensor means 45 is responsive tomovement of the solenoid 36 so as to provide an indication of whether ornot the solenoid 36 is operable to lock or release the detent.Obviously, other means could be adopted for the purpose of detecting thesolenoid condition.

If the drive motor 3 is energized to rotate the spindle 7 in the clutchrelease direction, the follower 18 will be caused to move along say thehelix track 16 and thereby lift the table 1. In that regard, the driveplate 30 is restrained against rotation by the detent ball 32 andconsequently the table is also held against rotation as it moves axiallyup the spindle 7. Operation of the motor 3 ceases when the table 1reaches the liimt of its upward travel and at that time the sample at aparticular station 9 is located within a respective vial 2. in thatregard, limit switches which form part of the motor control may bearranged for operation at the extremities of the axial travel of thetable 1.

In the arrangement shown optical sensors 42 and 43 (FIG. 1) detect whenthe table 1 is in its fully lowered and fully raised positionsrespectively. For that purpose the sensors 42 and 43 may respond to amark 44 provided on the sleeve 28. Another optical sensor (not shown)may function to monitor the rotational positions of the table 1.

More than one sample may be provided in the retaining means 11 at one ormore of the stations 9, but it will be convenient to refer to one sampleonly for the purpose of the present description. Each vial 2 contains anappropriate and respective solution for the purpose of processing theimmersed sample, and a different period of immersion may be required forsome of the solutions and/or samples. The control circuitry can bearranged to automatically attend to such differences. During theimmersion, the piezo crystals 15 are energized so as to produce suitableagitation of the associated samples.

At the end of the immersion period the control circuitry operates toagain turn the motor 3 in the clutch release direction. Since thefollower 18 is at the top of its travel it is caused to transfer to theother helix track 17 which then influences the follower 18, andconsequently the table 1, to move downwards. Rotation of the motor 3 inthe aforementioned direction ceases when the table 1 reaches itslowermost position as permitted by the cooperating follower 18 and helixtrack 17.

Assuming the apparatus is only part way through the processing of asample, it will be necessary to rotate the table 1 while in the loweredposition in order to place each vial 2 beneath a different samplestation 9. The control circuitry therefore causes the motor 3 to turn inthe clutch engaged direction so that the drive plate 30 will followrotation of the spindle 7. The driving force applied to the drive plate30 by the spindle 7 overcomes the resistance of the detent spring 39 sothat the ball 32 is cammed out of the recess 33 in which it was engaged.The detent ball 32 then tracks around the cylindrical surface 34 of thedrive plate 30 and locates in another recess to index the table 1 intoits next sample station position, at which time operation of the drivemotor 3 ceases.

When the table 1 has been indexed as described the control circuitrycommences to set in motion another sequence of operations as alsodescribed above.

It will be apparent from the foregoing description that the presentinvention provides a relatively simple yet effective apparatus forprocessing samples. The use of a single motor to perform severalfunctions is of particular advantage.

In a typical arrangement, there will be one example retainer 11 onlyattached to the cover member 8 and that will hold one or more samples tobe immersed sequentially in each of the vials 2. In that regard, thetable 1 may carry the maximum number of vials 2 allowed by theconstruction of that table 1 or it may carry a lesser number of suchvials 2 according to the requirements for the particular sample beingprocessed. Assuming a single circular row of sample stations 9 isprovided, there may be a plurality of sample retainers 11 in that rowlocated at suitably spaced intervals and each such interval will bridgea number of stations 9 equivalent to the maximum number of vials 2 inwhich a particular sample is to be immersed. If there is more than onerow of stations 9, each row may include one or more sample retainers 11,according to the requirements.

In a variation of the arrangement particularly described the sample maybe mounted on the table 1 and solutions for receiving those samplescould be mounted in any appropriate fashion relative to the table 1. Byway of example, mechanism may be operable to present each of severalsolutions in turn to a particular sample while the table is stationary,and the table is then rotated to allow processing of a further sample inthe same manner.

Various alterations, modifications and/or additions may be introducedinto the constructions and arrangements of parts previously describedwithout departing from the spirit or ambit of the invention as definedby the appended claims.

Having now described my invention what I claim as new and desire tosecure by Letters Patent is:
 1. Sample processing apparatus including, acarousel mounted for rotation and for back and forth movement in thedirection of the axis of said rotation, said carousel being in the formof a table which is adapted to carry a plurality of containers, a samplesupporting member overlying said carousel and arranged to carry at leastone sample so that the sample may be immersed in a said container whenthe carousel is in a raised position, and control mechanism operable tocause said rotation and said axial movement of the carousel, saidcontrol mechanism including, a drive motor which operates both in aforward mode and a reverse mode and transmission means whichinterconnects said carousel and said drive motor, said transmissionmeans being responsive to operation of said motor in one said mode tocause said carousel rotation and being responsive to operation of saidmotor in the other said mode to cause said carousel axial movement. 2.Apparatus according to claim 1, wherein the sample supporting member isin the form of a plate-like cover which is restrained against movementwith said table.
 3. Apparatus according to claim 1, wherein opticalsensor means is operable to detect both the rotational and axialpositions of said carousel.
 4. Apparatus according to claim 1, whereinagitating means is operable to cause movement of a said sample whileimmersed in a said container.
 5. Sample processing apparatus including,a carousel for carrying at least one of a sample and a container inwhich a sampale is immersible, said carousel mounted for rotation andfor back forth movement in the direction of the axis of said rotation,an upstanding rotatable spindle having a two-way helix formedtherealong, said carousel being mounted on said spindle, a followerconnected to said carousel and engaging with said helix so as tocooperate therewith and thereby cause said axial movement of thecarousel, and control mechanism operable to cause said rotation and saidaxial movement of the carousel, said control mechanism including, adrive motor which operates both in a forward mode and reverse mode andtransmission means which interconnects said carousel and said drivemotor, said transmission means being responsive to operation of saidmotor in one said mode to cause said carousel rotation and beingresponsive to operation of said motor in the other said mode to causesaid carousel axial movement.
 6. Apparatus according to claim 5, whereinretention means is operative to restrain said carousel against rotationwith said spindle when said motor is operating in said other mode. 7.Apparatus according to claim 5, wherein said transmission means includesa drive connection between said motor and said carousel, and said driveconnection includes said spindle and a one-way clutch between saidspindle and said carousel and which operates to allow said spindle torotate relative to said carousel in one direction and to prevent saidrelative rotation in the opposite direction.
 8. Apparatus according toclaim 7, wherein said drive connection includes a drive plate andcoupling means interconnecting said drive plate and said carousel so asto prevent relative rotation of said drive plate and carousel but permitrelative axial movement thereof, said one-way clutch acts between saidspindle and said drive plate, and said spindle rotates in response tooperation of said motor in either said mode thereof.
 9. Apparatusaccording to claim 8, wherein said coupling means includes a rod securedto said drive plate at a location radially outwards of said spindle andextending substantially in the axial direction of the spindle, and saidslidably engages with said carousel.
 10. Apparatus according to claim 8,wherein retention means is operative to restrain said drive plateagainst rotation with said spindle when said motor is operating in saidother mode.
 11. Apparatus according to claim 10, wherein said retentionmeans includes a spring loaded detent which is engagable with any one ofa plurality of indexing locators provided around said drive plate. 12.Apparatus according to claim 11, wherein a solenoid is operable toretain said detent against disengagement from a said locator. 13.Apparatus according to claim 12, wherein sensor means is operable todetermine whether said solenoid is operable or inoperable.